Summary: My program will begin by introducing the audience to the aquifers supplying groundwater to McHenry County’s wells and surface waters, illustrating the aquifers in maps and cross sections and describing the materials comprising the aquifers. I will then discuss the results of water-level, or head, mapping in the aquifers and the understanding of groundwater occurrence and movement gained from these mapping projects. ISWS researchers mapped water levels in the shallow aquifers of McHenry County in 1994 and 2011, and the ISWS has mapped of heads in the deep aquifers, across all of northeastern Illinois, about every five years since the late 1950s, most recently in late 2014 and early 2015. From 2009 to 2013, the ISWS, supported by geological modeling by the Illinois State Geological Survey, developed and applied a computer model to simulate groundwater flow in McHenry County, and the final part of the program will discuss the insights gained from this modeling, specifically with regard to the impacts of plausible scenarios of future pumping on head in the aquifers and on streamflow. I will then summarize the presentation content, discuss the relevance of this information for groundwater management in McHenry County, and offer directions for future work.

Scott joined the Illinois State Water Survey in August 1989. He earned B.S. with Honor and M.S. degrees in Geology from the University of Wyoming and the University of North Carolina at Chapel Hill, respectively, and is a Licensed Professional Geologist in Illinois. He has professional interest in stream base flow, groundwater recharge, and groundwater issues in northeastern Illinois and is an author or co-author of several publications on base flow and groundwater availability in northeastern Illinois.